For discussion of all the other girl+mecha lines that have cropped up since Shinki began: Frame Arms: Girls, Megami Device, Armor Girls Project, Desktop Army, etc. This includes kinda-sortas like Daibadi's Polynian and things like Strike Witches and Fumikane's original Mecha Musume.

I have a hard time spending $100 on a figure. Even the incredibly impressive Ultimate Madoka is cheaper than her. Sure she doesn't have quite as much plastic but she has an impressive paintjob and clear parts.

This makes me kind of wish I collected PVCs but alas, stationary figures aren't something I buy many of: